Many implantable medical devices, such as neurostimulators, pacemakers and defibrillators, transmit electrical signals to provide therapy to a patient. Electrical signals generated by the devices may be delivered to the patient tissue via electrodes disposed at a distal portion of a medical lead. The lead is electrically coupled to the device via a connector block or header of the device. The connector header includes a receptacle into which a lead may be inserted.
Typically, pins, which are electrically coupled to electronics of the device, are fed through a hermetically sealed housing of the device. The receptacle of the connector header contains conductive elements that are electrically coupled to the pins. The lead is insertable into the receptacle such that electrical contacts of the lead may be electrically coupled to the conductive elements of the receptacle. Conductors electrically couple the contacts of the lead to the electrodes.
Typical connector headers include a polyurethane housing and are made generally as follows. The lead receptacles are placed into the molded polyurethane housing or, alternatively, are placed into a polysulfone or other rigid polymeric frame over which the polyurethane housing is placed. Adhesive is used to bond the receptacles to the housing, the conductive elements of the receptacles are welded to the feedthrough pins, the housing is then filled with liquid silicone rubber or other suitable overmold or adhesive polymer, and the connector header housing is then secured to the housing of the device. As the lead receptacles are typically held together by a longitudinally compressive force, placement of the receptacles into the frame can be challenging. In addition, welding the conductive elements to the receptacle while in the frame can result in misalignment of the receptacle.